Doc fixes for propagate_grid() changes.

doc/tut_adaptive.rst

@@ -306,8 +306,16 @@ contiguously in row-major order:
    x(0.4) = 0.0232578
    v(0.4) = -0.14078
 
-There are no special requirements on the time values in the grid (apart from the
-fact that they must be finite and ordered monotonically).
+There are a few requirements on the time values in the grid:
+
+- they must all be finite,
+- they must be ordered monotonically,
+- the first value in the grid must be equal to the current
+  time of the integrator.
+
+.. versionchanged:: 4.0.0
+
+   The requirement on the first value of the time grid.
 
 .. versionadded:: 0.7.0
 

doc/tut_events.rst

@@ -380,7 +380,7 @@ execution of the callback:
 
 .. literalinclude:: ../tutorial/event_basic.cpp
     :language: c++
-    :lines: 136-145
+    :lines: 136-146
 
 .. code-block:: console
 

doc/tut_s11n.rst

@@ -168,12 +168,11 @@ example, again based on the simple pendulum:
 
 .. literalinclude:: ../tutorial/s11n_event.cpp
     :language: c++
-    :lines: 35-71
+    :lines: 35-69
 
 .. code-block:: console
 
    Number of events (original)    : 1
-   Number of events (after reset) : 0
    Number of events (from archive): 1
 
 The screen output indeed confirms that the event callback was correctly (de)serialised.

tutorial/adaptive_basic.cpp

@@ -110,9 +110,9 @@ int main()
 
     // Propagate over a time grid from 0 to 1
     // at regular intervals.
-    auto out = ta.propagate_grid({0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0});
+    auto out = ta.propagate_grid({0., 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0});
 
-    // Print the state at t = 0.4 (index 3 in the time grid).
-    std::cout << "x(0.4) = " << std::get<4>(out)[2 * 3] << '\n';
-    std::cout << "v(0.4) = " << std::get<4>(out)[2 * 3 + 1] << '\n';
+    // Print the state at t = 0.4 (index 4 in the time grid).
+    std::cout << "x(0.4) = " << std::get<4>(out)[2 * 4] << '\n';
+    std::cout << "v(0.4) = " << std::get<4>(out)[2 * 4 + 1] << '\n';
 }

tutorial/event_basic.cpp

@@ -134,6 +134,7 @@ int main()
     std::cout << "Event index        : " << static_cast<std::int64_t>(oc) << '\n';
 
     // Integrate over a time grid.
+    ta.propagate_until(1.);
     auto out = ta.propagate_grid({1., 2., 3., 4., 5., 6., 7., 8., 9., 10.});
 
     // Let's print the values of the state vector

tutorial/s11n_event.cpp

@@ -60,8 +60,6 @@ int main()
     // Reset ta to an integrator without events.
     ta = taylor_adaptive<double>{{prime(x) = v, prime(v) = -9.8 * sin(x)}, {0.05, 0.025}};
 
-    std::cout << "Number of events (after reset) : " << ta.get_nt_events().size() << '\n';
-
     // Restore the serialised representation of ta.
     {
         boost::archive::binary_iarchive ia(ss);